Low drop-out regulators (LDOs) refer to direct current (DC) voltage regulators or converters. Existing voltage regulators are complex, hard to design, and costly. For example, in an approach of an inductor based DC-DC voltage converter, both an inductor and a capacitor are used. The voltage converter provides high efficiency, but requires a large die area, and is therefore expensive.
In another approach of a continuous time LDO, a large power transistor and a compensation capacitor are used. The LDO provides a continuous output, but has lower efficiency. Additionally, circuit stability of the LDO is hard to control when the loads of the LDO vary.
Like reference symbols in the various drawings indicate like elements.